Nearly all countries are signatories of the CITES convention which controls the trade in animals and plants considered to be vulnerable to commercial exploitation. All species of monitor lizard are afforded protection under this legislation. It is not lawful to transport the animals across international boundaries without a CITES export certificate from the country of origin and a CITES import certificate from the country of destination. In order to obtain these certificates you must satisfy the authorities that the animals are in your possession legally. Commercial trade in species listed on Appendix I of the CITES regulations is totally outlawed and permits only given for their export and import for other purposes under exceptional circumstances.

Five Asian monitor lizards are included on Appendix I: the Komodo Dragon, Gray's monitor, the Bengal monitor, the Caspian monitor and the yellow monitor. All other species are listed in Appendix II. Commercial trade is allowed, but all specimens must carry CITES documentation. Failure to comply with CITES regulations results in automatic confiscation of the animals and punishments ranging from fines to imprisonment. Buyers of monitor lizards should always get a copy of the CITES import certificate authorising their import. If the lizards subsequently breed and you want to sell the youngsters abroad you will be expected to prove that they are captive bred and that the parent animals were legally imported. Some countries, notably Australia, only rarely issue export permits for wild animals and never for commercial trade (however see Hoser (1993b) for a fascinating account of the illicit trade in Australian wildlife). Goannas reach the rest of the world either for research and breeding exchanges between institutions, or illicitly. Luckily many specimens are intercepted at borders and passed on by the authorities to zoos and individuals who succeed in breeding them. Captive born Australian monitors with CITES certification fetch very high prices. In addition to CITES regulations local laws may impose separate restrictions or even prohibitions on the import and keeping of certain monitor lizards.

Butaan start to visit fruiting trees before they are large enough to
swallow the fruits. They make repeat journeys to trees, perhaps to
reinforce memory of the position of the tree. If the youngster survives
it may continue to use this tree for many decades. Fruiting trees like
this are a vital resource for entire populations of butaan. Learn more >

The butaan was first described to science in 1845 from a juvenile specimen collected by Hugh Cuming. It was labelled only "Philippines". It was named Varanus grayi. No other specimens came to light for over 120 years.
In the 1970s Walter Auffenberg found another specimen with a location
in Luzon, established that its correct scientific name was Varanus
olivaceus, and undertook a 22 month study of the species based in
Bicol. His study revealed that butaan occupy a unique ecological niche
and have a lifestyle quite unlike any other monitor lizard. Auffenberg used local hunters with dogs to catch the animals. Of 126
butaan caught
during his study, 116 animals were killed.